218 ILLINOIS ACADEMY OF SCIENCE 
on Citrus decumana, Rio Piedras (Stevenson), 2327; on 
Achras zapota, Rio Piedras (Stevenson), 3244. On Acrodic- 
tidium sahicifolium, Hormigueros 7360, 
Crustose lichens on leaves. 
Heterothecwum phyllocharis. 
Renealmia antillarum, Maricao, 743. 
THE OCCURRENCE OF ALTERNARIA IN A CHAR- 
TERISTIC APPLE SPOT, AND ANTAPPELE fou 
CAUSED BY GLIOCLADIUM VIRTDS 
By FRANCES JEAN MacINNES 
The twenty-five apples on which this work is based came 
from Harristown, Illinois, early in July, and were not nearly 
mature. The spots were in various stages of development, 
making it possible to study the probable progress of the disease. 
Nothing is known of the conditions under which they grew, 
nor of the time the infection started. 
THE DISEASE ON THE FRUIT 
The spot on the fruit is striking in its early stages, due to 
the decided color change and in the later stages to the distinct 
margin as well as the darkened skin and tissue. The outer 
skin of the diseased portion is tough and leathery, and diffi- 
cult to cut. Only a few millimeters beneath the skin are in- 
jured. The disease does not destroy a large part of the fruit, 
but it is unsightly, and would largely decrease salability. 
The earliest stage of the disease showed no softening of the 
tissue or change in the size or shape of the fruit. A spot about 
2 cm. in diameter was changed from green to a delicate yellow 
mottled with red. A later stage showed a spot slightly darker 
and mottled with both red and brown. What was considered a 
still more developed spot possessed the same characteristics as 
those above but in the center was a slightly sunken irregular 
brown spot with a distinct border. This spot was shiny, hard, 
and from 2 to 4 mm. in diameter. 
